1994-1995 Yamaha FX700 (FX1) Service Manual, Page 132Get this manual
IELECI I
STARTER MOTOR
2Remove: Armature ill Brush Brush holder Yoke assembly
M637000
INSPECTION
1Inspect: Commutator DirtY-7Clean it with #600 grit sand paper2Measure: Commutator diameter Out of specification-7Replace